Field of the Disclosure
The present disclosure is related to the medical field and, more particularly, to disposable syringes and removable sterile closures therefore used in the medical field, wherein the sterile closure is provided on the syringe during packaging, shipment, and storage of the syringe, and is then removed prior to use of the syringe.
Description of Related Art
Federal Food and Drug Administration (FDA) regulations require that the fluid path of a disposable syringe for administering therapeutic and diagnostic fluids to a patient be maintained in a sterile condition during shipment and storage of the syringe prior to its use. The conventional technique for maintaining the sterility of the fluid path is to enclose at least the portion of the syringe containing the fluid path in a blister pack seal with an indicating means, such as a foil label or sealing member, indicating the integrity of the seal. However, such blister packs are costly to produce and apply to the syringe during packaging. Further, a blister pack does not particularly conform to the structure of the syringe or the fluid path and, as such, is subject to damage and loss of seal during shipment and storage.
Within the prior art, a variety of alternative methods and devices for enclosing at least a portion of the syringe prior to its use have been developed. For example, U.S. Pat. No. 5,807,345 to Grabenkort discloses a luer cap configured for removably connecting to a male luer fitting at a discharge outlet of a syringe. The luer cap has an annular collar with internal threads that cooperate with the syringe luer fitting.
U.S. Pat. No. 6,394,983 to Mayoral et al. is directed to a cap and luer connector arrangement for a discharge outlet of a syringe. The connector has an inner sleeve with an inner surface configured for sealingly engaging a nozzle of the syringe. The connector is heat set to the syringe during an autoclave operation to prevent reinstallation of the connector once removed.
U.S. Pat. No. 6,632,199 to Tucker et al. is directed to a syringe assembly that includes a plastic cap and the discharge outlet of the syringe. The cap engages a luer fitting on the syringe to create a tight, sealing interference fit between the cap and the syringe. The cap provides a seal at two different points on the syringe: around the outside of the luer collar and inside the luer opening.
U.S. Pat. No. 7,367,964 to Heinz et al. is directed to a syringe having an open free end enclosed by a cap. The cap engages the free end of the syringe by interacting with the internal thread of a syringe connection formed at the free end.
While a variety of methods and devices for enclosing at least a portion of the syringe prior to its use have been proposed in the prior art, it is difficult to provide a method and device that maintains sterility of the discharge outlet of the syringe and its surrounding structure in various applications and under a variety of circumstances. For example, existing cap designs do not allow for venting of pressure inside the syringe. Venting of the pressure inside the syringe is an important design consideration because excess pressure may cause the plunger to move from its desired initial position, such as its position when the syringe is pre-filled with a fluid. Designs that incorporate a venting feature are overly complex and prohibitively expensive to use. It would be advantageous to provide a sterility enhanced closure for a fluid path of a syringe that maintains sterility of various components at the discharge outlet of the syringe.